CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
CURRENT ASSETS:
Cash and cash equivalents	$ 93,655	$ 62,134
Short-term marketable securities	189,236	188,323
Accounts receivable, net of allowance for doubtful accounts of $734 and $525 in 2017 and 2016, respectively	16,798	6,528
Inventories	57,087	52,564
Prepaid expenses and other current assets	7,758	8,715
Total current assets	364,534	318,264
PROPERTY AND EQUIPMENT, net	111,705	95,296
INTANGIBLE ASSETS, net	25,419	31,502
GOODWILL	91,849	91,849
DEFERRED TAX ASSETS	2,364	11,342
OTHER ASSETS	25,203	6,157
Total assets	621,074	554,410
CURRENT LIABILITIES:
Accounts payable	33,211	29,727
Accrued payroll and related expenses	12,064	10,756
Taxes payable	1,767	729
Other accrued liabilities	4,009	2,734
Total current liabilities	51,051	43,946
LONG-TERM INCOME TAXES PAYABLE	18,259	2,639
DEFERRED TAX LIABILITIES	138	820
OTHER LIABILITIES	3,944	3,921
Total liabilities	73,392	51,326
STOCKHOLDERS’ EQUITY:
Common stock, $0.001 par value Authorized - 140,000,000 shares Outstanding - 29,782,455 and 29,249,635 shares in 2017 and 2016, respectively	29	28
Additional paid-in capital	198,384	172,875
Accumulated other comprehensive loss	(2,139)	(2,710)
Retained earnings	351,408	332,891
Total stockholders’ equity	547,682	503,084
Total liabilities and stockholders’ equity	$ 621,074	$ 554,410